Knee extension device



FIG. 1 is a perspective view of the knee extension device showing our new design.

FIG. 2 is a right side view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a front end view thereof;

FIG. 5 is a rear end view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The partial leg and foot depicted in dash-dot-dot-dash broken lines, and the hand grip and knee pad depicted in evenly-spaced broken lines form no part of the claimed design. 

CLAIM We claim the ornamental design for a knee extension device, as shown and described. 